In the x-ray cassette holder field, it is a desirable objective to provide a user-friendly x-ray cassette holder and positioning device wherein the positioning device is characterized by: as few adjustments as possible; wherein the x-ray cassette holder and positioning device allows a high volume of radiography in a variety of environmental situations; and wherein the design of such a user-friendly x-ray cassette holder and positioning device is capable of being used with portable x-ray machines having different sizes, weights and configurations.
U.S. Pat. No. 4,455,672 discloses a cassette holder assembly for an x-ray examination apparatus comprising a housing, cassette holder means associated with the housing and having oppositely adjustable clamping jaw means for the centric clamping of x-ray film cassettes of varying format, spring means for drawing the clamping jaw means toward one another, an actuating handle displaceable on the housing of the cassette holder means, an actuating frame movably mounted by the housing and coupled with the handle for movement in a given direction when manual force is applied to the handle for the purpose of moving the clamping jaw means toward a release condition; the clamping jaw means comprising a first clamping jaw connected with the actuating frame for movement toward a release condition as the actuating frame is moved in the given direction, and lever means comprising a lever pivotally mounted on the housing intermediate the ends of the lever and having a first end coupled with the actuating frame and a second end for moving oppositely to the actuating frame, the clamping jaw means comprising a second clamping jaw disposed opposite the first clamping jaw and coupled with the second end of the lever so as to move oppositely to the first clamping jaw as the actuating frame is moved in said given direction; the handle thereby being manually actuatable to move the first and second clamping jaws away from each other against the action of the spring means.
An x-ray film cassette holder is depicted in U.S. Pat. No. 4,538,293, wherein the x-ray film cassette holder includes a clamping mechanism for positioning a film cassette therein as the holder is inserted into an associated x-ray machine, and two linear potentiometers for sensing the dimensions of the film cassette. The clamping mechanism has two positioning assemblies which act to position the film cassette in two orthogonal directions and an actuator assembly that links the positioning operation to the insertion movement, all mounted on a tray that is adapted for insertion into the x-ray machine.
An x-ray apparatus comprising a film cassette which is displaceable in a carriage is disclosed in U.S. Pat. No. 4,961,213. The x-ray apparatus comprises, in combination: a support; a carriage for a film cassette displaceable in a load direction; a cassette clamp device for positioning the cassette perpendicularly to the load direction; a plurality of pairs of guide rollers offset with respect to one another in the load direction on the support and on the carriage; independently controlled motor drives which act on the clamp device via an endless loop traction means set forth guided via the rollers, the traction means sections between the rollers on the carriage being parallel to one another and between the rollers on the support being parallel to one another; and the endless loop traction means forming a closed loop which is movable relative to the support throughout the loop guided from one roller of a roller pair mounted on the support to the other roller of the pair via one of the pairs of rollers on the carriage, the loop being coupled to the clamp device for fixing the cassette position, two motor drives acting on the traction means via the rollers on the support, between said rollers on said support there being situated at least one roller which is not secured to the support.
However, in the foregoing x-ray film cassette holder apparatus of the prior art, there is an absence of any apparatus which utilizes a one-lever/handle element to provide positioning and size adjustment for five x-ray cassette sizes in both vertical and horizontal directions.